Phonograph pick-up apparatus



Ot- 14, 1930- n J. DIEUX 1,778,211

PHONOGRAPH PICK-UP APPARATUS Filed OGL. 20, 1928 Patented oct. 14, 1930 JnaN DIEUx, or rams, ramon n rnoxoemn rmx-U1 Arrm'rus Application med October-20,1988, Serial No. $118,100, and in France December v8,v 1087i lMy invention relates to electro-magnetic pick-up apparatus for the conversion of the mechanical vibrations of a stylus resting in v the grooves of a phonograph or like record Minto corresponding electric oscillations. y

The object of the invention is to amplify the vibrationsof thev moving armature so as l*to increase the variations of themagnetic `field and the corresponding sonorous vibra- 10 tions.

A further' object comprises the ra id dampin in as sim le a manner as possi le, of the vibrations o the moving armature so as to avoid the superposition of these vibra- 15 tions on the armature, which would beA detrimental toits working.

These objects are attained by 'providing the apparatus with the characteristic features of the following s ecification, and par- 20 ticularly, those set yfort` in the accompany ing claims.

The preferred form of the invention is shown somewhat diagrammatically in the 2 are, respectively, a vertical elevation and a plan of Yan electromagnetic pick-up withv as shown at 16, Fig. 1, so as to rei-inforce the action of the'magnetic field ofthe elec tromagnet 2, 3. The moving armature 1 is bent at 7 to provide a vertical arm 12 which carries the stylus 8 which rests on the phonograph record 9.

The vertical arm 12 extends through and' is engaged in a plu 10 formed of a pliant,

elastic or flexible su stance, such as rubber.`

This plug forms a damper, and it also closes Athe casing 11 which contains and supports the aforesaid parts.

5 The moving armature is also provided the oscillations of the moving armature 1.

accompanying drawings, wherein Figs 1 and l -tion near. the coil of said e with a vertical extension' ll whichlcombined with the vertical arm 12 gives the saidarma-l ture the form of the letter T lying on its side in a vertical plane. This vertical extension, 1a is engaged in a rin 1* also formed of a pliant, elastic or flexib e material.- The ring 1s connected with the casing 11 by a su port 17 and co-operates with the plug 10 to damp vThe aforesaid electric pick-up has numer-I c. ous advantages. Firstly, the'vibrations of 4 the stylus 8, under the action of the grooves inthe record 9, are amplified by the horizontal lever arml1 of the armature, and this produces considerable variations in the flux u of the electromagnet and perceptible varia- 'tions in the current passing through its windin. y c I oreover, the vibrations ofthe stylus are very rapidly damped by the combined action ofy the two dampers 10 and 14, which are placed on either side of the horizontal arm r11 of the moving armature. c

These dampers serve also as a support yfor the moving armature, .so that known supporting devices including pivots, forks, etc., which are usually complicated v and fragile devices, can be dispensed with. What I claim as my invention and desire to secure` by Letters Patent'is 1. In an electromagnetic phonograph pick up apparatus, an electromagnet, a moving ,c armature bent so as to form two arms, one of n' said arms moving in the magnetic field of said electromagnet, and having an expanded pora5 ectromagnet, va stylus mounted on the other arm of said moving armature so as to engage withthe surface of the phonograph record, the vibrations of said stfylus being amplified by the first named arm -un said moving armature.

2. In an electromagnetic phonograph pick@ up apparatus, an electromagnet, a moving armature bent so as to form two arms, one arm moving in the magnetic field of said elec- '-96 tromagnet and being thickened near the coil of said electromagnet, a stylus mounted on the'y vother arm of said moving armature so as to engage with the surface of the l phonograph record the vibrations of said stylus being axn- 101 plifed by the first named arm of said moving armature.

3. In an electromagnetic phonograph pickup apparatus, an electromagnet, a moving armature bent so as to form two arms, one of said arms moving in the magnetic field of said electromagnet, the other arm being substantially perpendicular to the first named arm and having an extension so as to form a T with the first named arm, and guiding means being provided on said other arm and the extension of this other arm, a stylus mounted on the other arm of the moving armature and adapted to engage with the surface of the phonograph record, the vibrations of the stylus being amplified by the first said arm of said moving armature. Y

4; In'an electromagnetic phonograph pickup apparatus, an electromagnet, a moving armature bent so as to form two. arms, one ofsaid arms moving in the magnetic field of said electromagnet, a stylus mounted on the second arm of said moving armature and engagingkwith the grooves of the phonograph record, the vibrations ofthe stylus being amplified 'by the first mentioned arm of said moving armature', andtwo supports of flex` ible material suspending jsaid moving arma'- ture at two different places and damping the vibrations thereof.

5. In an electromagnetic phonograph pick- 'up apparatus,,an electromagnct, a moving armature bent so as toA form two arms, one of v said'arms moving in the magnetic field of said electromagnet and the other arm being sub' stantially perpendicular to the first said arm,

and having an extension sofas to form a T' with the first said arm, a stylus mounted on said other arm and adapted to engage with the surface of the phonograph record, the

vibrations of said stylus being amplifled'by and having an extension forming and engaging said armature to damp the vibrations thereof, and a ring of resilient material engaging said armature and coo erating with said plug to damp the vibrations of said armature.v

up apparatus, an electromagnet, a moving armature bent so as to provide two'arms, one of said arms moving inthe magnetic field of said electromagnet, the other arm being substantially perpendicular to the first said arm,

a T with the first said arm, a stylus mounte on the other arm of said armature and engaging with the surface of the phono raph record, the vibrations of said stylus eing amplified by the first said arm of lsaid-armature, a casing con- 8. In an electromagnetic phonograph pick; 7o

taining the said partsz a plug offiexible mate-l rial closing said casing and engagmg said V other arm of said armature, and a ring offiexible material carried by said casing and en gaging the extension of said other arm of said armature, said 'ring cooperating with said plug to ,damp the vibrations of said armature. v

In testimony ,WhereofI have signed this specification.

. .JEAN DIEUX.

vthe first said arm ofV said moving armature,

"and two supports of pliant material mounted,

one on said other arm of the moving armature and the other on the said extension of 4said arm, said two supports carrying the suspended moving armature at two difl'erentplaces and damping the vibrations thereof.

6. In an electromagnetic phonograph picku apparatus, an electromagnet, an armature a a ted to vibrate in rthe magnetic field of' sai electromagnet, a stylus mounted on said moving armature so as to engage with the grooves of the phonograph record,l a casing .containing said arts, a plug of pliant material closing sai casing and engaged on theA 1 l ne moving armature to damp the vvibrations .Y

thereof. v 7 In an electromagnetic phonograph pickup apparatus, an electromagnet, a. moving armature'in the magnetic field of said electro# magnet, a stylus mounted' on said armature so las v'as to engage with the surface of the phono' i -g'raph record, a casing'containing parts, a plug of resilient material closing said casing uso 

